Um, are we talking trade secrets or simple ways... wrecker driver will have a wedge and a long rod that he wedges into the top back corner of the door frame to create an opening and taking the rod, usually about 6' long 3/16" thinck and slightly curved will reach in and hit the power lock button...
Well, that is how I do it... alot cheaper than the lockout kit I have, and gets used 95% of the time!
It stays away from the wiring inside, so really no damage if your careful, and if your worried about the paint, use some tape around the area before you start on it...